1. Technical Field
The present invention relates to an information sharing apparatus and an information sharing system that facilitate connecting with each other at multiple sites via a network and sharing handwriting and a screen with each other.
2. Background Art
Electronic information board apparatuses that include a large-sized flat panel display (approximately 40-60 inches) such as LCD and plasma display or use a projector equipped with a touch panel are now commercially available. These apparatuses can display a large-scale version of the screen of a connected PC and are widely used at presentations and meetings, etc., at companies, administrative agencies, educational institutions, and the like.
Usually, this kind of electronic information board apparatus operates the PC that displays the screen by touching the displayed screen using a touch panel function instead of operating a mouse, thereby facilitating operating the PC via the touch panel as a PC operating function via the touch panel. Furthermore, electronic whiteboard application software that runs on the connected PC is also provided along with these apparatuses. The electronic information board apparatus provides a screen that acts as a whiteboard in combination with the application software, and functions such as writing by hand on the screen via the touch panel and superimposing handwriting on the screen of the PC that runs the application are provided as a handwriting function via the touch panel.
Alternatively, an information sharing apparatus that facilitates teleconferences connecting these electronic information board apparatuses at multiple sites via a network such as internet and intranet, talking over the phone, and sharing each other's handwriting and screens is provided. With this kind of information sharing apparatus, participants in the teleconference can share lots of information with each other, which contributes to wrapping up the conclusion effectively by reviewing the content of the shared screens and reusing them at the end of the teleconference.
However, in this kind of information sharing apparatus that includes the teleconferencing function, there is delay of at least a network transmission time Δt between displaying handwriting at the handwriting sender and at the handwriting receiver. Therefore, if the handwriting sender starts displaying at t0, the handwriting receiver starts displaying at t0+Δt, so there is a problem that the handwriting sender cannot know when the handwriting receiver starts displaying. Especially since the handwriting sender cannot see the receiver's reaction such as a nod over the telephone, the handwriting sender feels anxious about displaying the handwriting at the handwriting receiver's side, and that prevents participants from participating in the teleconference interactively.
For example, a technology of flashing handwriting at the receiver's side in order to promote interactive usage of handwriting at teleconferences has been proposed (e.g., JP-H06-284240-A.) Also, a technology of displaying symbols that indicate to the handwriting receiver that the handwriting sender is writing something by hand has been proposed (e.g., JP-2011-151613-A.) However, these technologies cannot solve the problem that the handwriting sender cannot know whether or not the handwriting is displayed at the handwriting receiver's side.